<template>
	<view class="u-wrap">
		<view class="u-search-box" style="position: fixed;width: 95%;z-index: 999;background-color: rgb(234 234 234);">
			<view class="u-search-inner">
				<u-search placeholder="商品名称" v-model="keyword" @clear="claer" @custom="searchGoods"></u-search>
			</view>
		</view>
		<u-row gutter="12">
			<u-col span="3">
				<view class="u-menu-wrap" style="position: fixed;top:100px">
					<scroll-view @scroll="loadmore" lower-threshold='50' scroll-y scroll-with-animation class="u-tab-view menu-scroll-view"
						:scroll-top="scrollTop">
						<view v-for="(item,index) in tabbar" :key="item.id" class="u-tab-item"
							:class="[current==item.id ? 'u-tab-item-active' : '']" :data-current="item.id"
							@tap.stop="swichMenu(item.id)">
							<text class="u-line-1">{{item.name}}</text>
						</view>
					</scroll-view>
				</view>
			</u-col>
			<u-col span="9" >
				<view  style="margin-bottom: 100px;margin-top: 40px;">
				<view class="u-text-center" style="margin-top: 30px;">
					<u-tabs :list="sortList" lineWidth="40rpx" itemStyle='width:17%;height:35px' :current='currentSort'
						@change="changeSort"></u-tabs>
				</view>
					<goods-cart :goods='goodsList' :loading='false'></goods-cart>
					<u-loadmore :status="status" @loadmore='loadmore' />
				</view>
				<view v-if='goodsList.length===0'>
					<view class="u-flex-1" style="margin-top: -390px;">
						<u-empty mode="list" icon="http://cdn.uviewui.com/uview/empty/car.png"></u-empty>
					</view>
				</view>
			</u-col>
		</u-row>
	</view>
</template>

<script>
	//	import classifyData from "@/common/classify.data.js";
	export default {
		data() {
			return {
				tabbar: [],
				currentSort: 0,
				sortList: [{
					name: '默认'
				}, {
					name: '销量'
				}, {
					name: '推荐'
				}, {
					name: '最新'
				}],
				goodsList: [],
				keyword:'',
				status:'loadmore',
				page:1,
				scrollTop: 20, //tab标题的滚动条位置
				current: null, // 预设当前项的值
				menuHeight: 0, // 左边菜单的高度
				menuItemHeight: 0, // 左边菜单item的高度
			}
		},
		onLoad() {
			this.getGoodsList()
		},
		methods: {
			//tabs点击
			changeSort({index}) {
				this.currentSort = index
				//重置商品数据
				this.goodsList = []
				this.page = 1
				//筛选条件
				this.getGoodsList()
			},
			//获取商品
			async getGoodsList() {
				const params =　{
					page: this.page,
					title:this.keyword
				}
				if (this.currentSort == 1) params.sales = 1
				if (this.currentSort == 2) params.recommend = 1
				if (this.currentSort == 3) params.new = 1
				if(this.current){
					params.category_id = this.current
				}
				let res = await this.$u.api.goodsList(params)
				this.goodsList = this.goodsList.concat(res.goods.data)
				this.tabbar = res.categories
				this.status = res.goods.next_page_url?'loadmore':'nomore'
			},
			//搜索商品
			searchGoods(){
				this.page = 1
				this.goodsList = []
				this.getGoodsList()
			},
			//清空搜索框
			claer(){
				this.page = 1
				this.keyword = ''
				this.goodsList = []
				this.getGoodsList()
			},
			//加载更多
			loadmore(){
				this.page +=1
				this.status = 'loading'
				this.getGoodsList()
			},

			getImg() {
				return Math.floor(Math.random() * 35);
			},
			// 点击左边的栏目切换
			async swichMenu(id) {
				this.current = id
				
				this.goodsList = []
				this.getGoodsList()
				
				if (id == this.current) return;
				this.current = id;
				// 如果为0，意味着尚未初始化
				if (this.menuHeight == 0 || this.menuItemHeight == 0) {
					await this.getElRect('menu-scroll-view', 'menuHeight');
					await this.getElRect('u-tab-item', 'menuItemHeight');
				}
				// 将菜单菜单活动item垂直居中
				this.scrollTop = id * this.menuItemHeight + this.menuItemHeight / 2 - this.menuHeight / 2;
			},
			// 获取一个目标元素的高度
			getElRect(elClass, dataVal) {
				new Promise((resolve, reject) => {
					const query = uni.createSelectorQuery().in(this);
					query.select('.' + elClass).fields({
						size: true
					}, res => {
						// 如果节点尚未生成，res值为null，循环调用执行
						if (!res) {
							setTimeout(() => {
								this.getElRect(elClass);
							}, 10);
							return;
						}
						this[dataVal] = res.height;
					}).exec();
				})
			}
		}
	}
</script>

<style lang="scss" scoped>
	
	page{
	    width:100%;
	    height:100%;
	}

	scroll-view{
		height: 100px
	}
	.u-wrap {
		height: calc(100vh);
		/* #ifdef H5 */
		height: calc(100vh - var(--window-top));
		/* #endif */
		display: flex;
		flex-direction: column;
	}

	.u-search-box {
		padding: 18rpx 30rpx;
	}

	.u-menu-wrap {
		flex: 1;
		display: flex;
		overflow: hidden;
	}

	.u-search-inner {
		background-color: rgb(234, 234, 234);
		border-radius: 100rpx;
		display: flex;
		align-items: center;
		padding: 10rpx 16rpx;
	}

	.u-search-text {
		font-size: 26rpx;
		color: $u-tips-color;
		margin-left: 10rpx;
	}

	.u-tab-view {
		width: 200rpx;
		height: 100%;
	}

	.u-tab-item {
		height: 110rpx;
		background: #f6f6f6;
		box-sizing: border-box;
		display: flex;
		align-items: center;
		justify-content: center;
		font-size: 26rpx;
		color: #444;
		font-weight: 400;
		line-height: 1;
	}

	.u-tab-item-active {
		position: relative;
		color: #000;
		font-size: 30rpx;
		font-weight: 600;
		background: #fff;
	}

	.u-tab-item-active::before {
		content: "";
		position: absolute;
		border-left: 4px solid green;
		height: 32rpx;
		left: 0;
		top: 39rpx;
	}

	.u-tab-view {
		height: 100%;
	}

	.right-box {
		background-color: rgb(250, 250, 250);
	}

	.page-view {
		padding: 16rpx;
	}

	.class-item {
		margin-bottom: 30rpx;
		background-color: #fff;
		padding: 16rpx;
		border-radius: 8rpx;
	}

	.item-title {
		font-size: 26rpx;
		color: $u-main-color;
		font-weight: bold;
	}

	.item-menu-name {
		font-weight: normal;
		font-size: 24rpx;
		color: $u-main-color;
	}

	.item-container {
		display: flex;
		flex-wrap: wrap;
	}

	.thumb-box {
		width: 33.333333%;
		display: flex;
		align-items: center;
		justify-content: center;
		flex-direction: column;
		margin-top: 20rpx;
	}

	.item-menu-image {
		width: 120rpx;
		height: 120rpx;
	}
</style>
